drain gulley in conservatory

[philrosenberg]

Hi
I'm looking for some advice about a covering/sealing a drain gulley (U-bend which then goes into the underground drains) that is inside my conservatory as shown below- please don't mock the plumbing it is on my to do list

Untitled

• philrosenberg
• 4 Jan 2010
• 1

The gulley takes all the house's grey water (Kitchen sink, dishwasher, bath, basin and washing machine) and I'd like to box it in if possible. Ideally I'd like to seal it up completely to keep out any smells and also so that if the drains ever get blocked the conservatory is not inundated with sewage.
I'd like to know if I can safely seal it up? Do I need to provide some sort of vent to avoid syphoning and if so can this vent run horizontally under the floor then up an external wall? (I'm intending to put a new floating floor down on top of 50 mm of insulation so could easily run a vent pipe under the floor)

Thanks in advance for any help

Phil

 

[Hugh Jaleak]

Various options, depends how technical you want to get. Simplest option, fabricate some sort of cover for existing setup.

More complicated, dig out existing gulley Then either replace with a new plastic bottle gulley and replace grating with a sealed lid. Boss the waste pipes into side or rear of new gulley. Or fit a stub stack with access cover, boss pipes into stub stack. Either will prevent backup of sewage in the event of blockage and allow access for rodding should it be needed. Doubt you'd need any form of vent.

 

[Richard C]

I had one of those; I’m sure you really don’t want even a sealed gulley & a mess of pipes visible in your new cons. or even a sealed hatch, I know I didn’t.

Rip it all out & extend through the wall to provide a new stub stack inside (mine’s under the sink) & connect your services up to that, with suitable traps & access of course. Yours is a little more involved as you’ve got additional bathroom waste (is it ground floor?) but assuming there is a w/c, where does that discharge? If you’ve a stack you would be better re-routing the bath/sink waste to that. You may need to vent individual waste runs, depending on length but it’s easily done.

 

[philrosenberg]

Thanks for the info. I'd never heard of stub stacks.
Moving the drain inside isn't an easy option as we have solid concrete floors and if this drain is similar to another one that I moved then it'll be about 3 ft deep which makes it much more than a weekend job. If needs be I can box most of it in.
I've done a bit of googling on stub stacks an I've a couple of other questions. First do I need an air admitance valve on the stub stack. Secondly does it make any difference if I leave the existing gulley and put the stub stack into this or dig it out and put the stub stack directly into the drains? The first option would be much less work, but if it's a bad option I'll get my pick axe out.

Thanks
Phil

 

[powell30]

JUst be aware any alteration to drainage systems is covered under building regs........so you'll need to apply for a certificate to confirm it conforms.....call your local planning office, they are very helpful and may have some suggestions that will save you time, money or effort.....or all three!

 

[Richard C]

Moving the drain inside isn't an easy option as we have solid concrete floors and if this drain is similar to another one that I moved then it'll be about 3 ft deep which makes it much more than a weekend job.

I didn’t say it was easy; it’s bloody hard work, particularly if you’re not used to it but if you’ve done it before you’ll know what to expect. It’s the proper way to do it.

If needs be I can box most of it in.

That will look terrible IMO & not very hygienic; cons don’t need Building Regs. (apart from safety glass & electrics) but if they did, just boxing it in would not comply. The minimum you should have is a double seal inspection hatch & if your going to the trouble of putting one of those in, you might as well get the SDS breaker out & holes through the slab & the walls; forget the pick axe, you will be there forever.

First do I need an air admitance valve on the stub stack.

My stub stack terminates around 3 inches above the floor within the kitchen unit plinth, the sink waste discharges directly into the top & the dishwasher waste tees into the sink waste via a 3 in 1 trap; I do not have an AAAV. You have additional waste runs which, depending on length, (3 metres for 40mm 5m for 50mm) & how you connect them may need venting but this can be done locally using either a smaller AAAV or an anti-siphon trap; without know the layout & length of these runs, I cant say.

Secondly does it make any difference if I leave the existing gulley and put the stub stack into this or dig it out and put the stub stack directly into the drains? The first option would be much less work, but if it's a bad option I'll get my pick axe out.

I see little point in doing that as it will all still be visible, look bloody awful & will not be sealed against smells; doing it properly just involves a days hard work, some plastic pipe & fittings & a little concrete; not much extra effort IMO but it’s your choice.

Have a look at Part H Building Regs. for guidance & to ensure what you do complies with Regs;
http://www.planningportal.gov.uk/uploads/br/BR_PDF_ADH_2002.pdf
You should also ring your LABC & explain what you are doing but if your just modifying the existing arrangement & not making a new connection to the foul drain, they probably won't be interested.

 

[philrosenberg]

Hi Richard
Thanks for the advice. As soon as i get a free weekend I'll get it all sorted.

Thanks again and thanks to the others who replied.

Phil